The management of solid waste is one of the challenges facing any urban area in the world. An aggregation of human settlements has the potential to produce a large amount of solid waste; the collection, transfer and disposal of that waste has been generally assumed by municipal governments in the developed world. Municipal solid waste (MSW) management has become a major issue of concern for many under-developed nations, however, especially as populations increase.
Solid waste is broadly defined as including non-hazardous industrial, commercial and domestic refuse including household organic trash, street sweepings, hospital and institutional garbage, and construction wastes; generally sludge and human waste are regarded as a liquid waste problem outside the scope of MSW. Schübeler (1996) points out that although certain contaminated medical wastes and hazardous industrialwastes are not included by definition, in many nations these are in fact part of the municipal waste stream and “special measures” must be employed to encourage their separation and mitigate their potential harmful effects. Also, the threat of toxic waste being present in industrial garbage often leads to it being treated separately, although this is not always the case.
Is a decomposable waste from food.
Is a nondecomposable waste, either combustible (such as paper, wood, and cloth) or noncombustible (such as metal, glass and ceramics)
Are residues of the combustion of solid fuels.
Is a demolition and construction debris and trees.
Sewage –Treatment solids
Are materials retained on sewage-treatment screens, settled solids, and biomass sludge.
Includes materials as chemicals, paints and sand.
Are Farm animal manure and crop residues.
Includes computer, its parts and chemicals.
Harazardous wastes have been defined as wastes that pose a potential hazard to humans or other living organisms for one or more of the following reasons:
- Such wastes are nondegradable or persistent in nature
- Their effects can be magnified by organisms in the environment
- They can be lethal
- They may cause detrimental cumulative effects. General categories of hazardous wastes include toxic chemicals and flammable, radioactive, or biological substances. These wastes can be in the form of sludge, liquid, gas and solid.
They are hazardous because prolonged exposure to ionizing radiation often results in damage to living organisms, and the substances may persist over long periods of time.